1. Field of the Invention
The present invention relates to a hollow actuator including a hollow portion.
2. Discussion of the Background
Industrial robots have been increasingly used to assemble automobiles on automobile assembly lines and to assemble other components with or without human intervention. In order to realize such a robot, a hollow actuator is used. As described in Japanese Examined Utility Model Registration Application Publication No. 7-42215 and Japanese Unexamined Patent Application Publication No. 2006-149139, a hollow actuator includes a reduction gear mechanism and an AC servo motor having a hollow shaft.